1 files changed, 165 insertions, 0 deletions
diff --git a/src/uri-references.cpp b/src/uri-references.cpp
new file mode 100644
index 000000000..fff985139
--- /dev/null
+++ b/src/uri-references.cpp
@@ -0,0 +1,165 @@
+#define __SP_URI_REFERENCES_C__
+
+/*
+ * Helper methods for resolving URI References
+ *
+ * Authors:
+ *   Lauris Kaplinski <lauris@kaplinski.com>
+ *
+ * Copyright (C) 2001-2002 Lauris Kaplinski
+ * Copyright (C) 2001 Ximian, Inc.
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include "document.h"
+#include "sp-object.h"
+#include "uri.h"
+#include "uri-references.h"
+
+static gchar *uri_to_id(SPDocument *document, const gchar *uri);
+
+namespace Inkscape {
+
+URIReference::URIReference(SPObject *owner)
+: _owner(owner), _obj(NULL), _uri(NULL)
+{
+	g_assert(_owner != NULL);
+	/* FIXME !!! attach to owner's destroy signal to clean up in case */
+}
+
+URIReference::~URIReference() {
+	detach();
+}
+
+void URIReference::attach(const URI &uri) throw(BadURIException)
+{
+	SPDocument *document = SP_OBJECT_DOCUMENT(_owner);
+	gchar const *fragment = uri.getFragment();
+	if ( !uri.isRelative() || uri.getQuery() || !fragment ) {
+		throw UnsupportedURIException();
+	}
+
+	/* FIXME !!! real xpointer support should be delegated to document */
+	/* for now this handles the minimal xpointer form that SVG 1.0
+	 * requires of us
+	 */
+	gchar *id;
+	if (!strncmp(fragment, "xpointer(", 9)) {
+		/* FIXME !!! this is wasteful */
+		/* FIXME: It looks as though this is including "))" in the id.  I suggest moving
+		   the strlen calculation and validity testing to before strdup, and copying just
+		   the id without the "))".  -- pjrm */
+		if (!strncmp(fragment, "xpointer(id(", 12)) {
+			id = g_strdup(fragment+12);
+			size_t const len = strlen(id);
+			if ( len < 3 || strcmp(id+len-2, "))") ) {
+				g_free(id);
+				throw MalformedURIException();
+			}
+		} else {
+			throw UnsupportedURIException();
+		}
+	} else {
+		id = g_strdup(fragment);
+	}
+
+	/* FIXME !!! validate id as an NCName somewhere */
+
+	if (_uri) {
+		delete _uri;
+	}
+	_uri = new URI(uri);
+
+	_connection.disconnect();
+	_setObject(document->getObjectById(id));
+	_connection = document->connectIdChanged(id, sigc::mem_fun(*this, &URIReference::_setObject));
+
+	g_free(id);
+}
+
+void URIReference::detach() {
+	_connection.disconnect();
+	delete _uri;
+	_uri = NULL;
+	_setObject(NULL);
+}
+
+void URIReference::_setObject(SPObject *obj) {
+	if ( obj && !_acceptObject(obj) ) {
+		obj = NULL;
+	}
+
+	if ( obj == _obj ) return;
+
+	SPObject *old_obj=_obj;
+	_obj = obj;
+
+	if (_obj) {
+		sp_object_href(_obj, _owner);
+		g_signal_connect(G_OBJECT(_obj), "release", G_CALLBACK(&URIReference::_release), reinterpret_cast<gpointer>(this));
+	}
+	_changed_signal.emit(old_obj, _obj);
+	if (old_obj) {
+		/* release the old object _after_ the signal emission */
+		g_signal_handlers_disconnect_by_func(G_OBJECT(old_obj), (void *)&URIReference::_release, reinterpret_cast<gpointer>(this));
+		sp_object_hunref(old_obj, _owner);
+	}
+}
+
+/* If an object is deleted, current semantics require that we release
+ * it on its "release" signal, rather than later, when its ID is actually
+ * unregistered from the document.
+ */
+void URIReference::_release(SPObject *obj, URIReference *reference) {
+	g_assert( reference->_obj == obj );
+	reference->_setObject(NULL);
+}
+
+} /* namespace Inkscape */
+
+static gchar *
+uri_to_id(SPDocument *document, const gchar *uri)
+{
+	const gchar *e;
+	gchar *id;
+	gint len;
+
+	g_return_val_if_fail (document != NULL, NULL);
+
+	if (!uri) return NULL;
+	/* fixme: xpointer, everything */
+	if (strncmp (uri, "url(#", 5)) return NULL;
+
+	e = uri + 5;
+	while (*e) {
+		if (*e == ')') break;
+		if (!isalnum (*e) && (*e != '_') && (*e != '-') && (*e != ':') && (*e != '.')) return NULL;
+		e += 1;
+		if (!*e) return NULL;
+	}
+
+	len = e - uri - 5;
+	if (len < 1) return NULL;
+
+	id = (gchar*)g_new(gchar, len + 1);
+	memcpy (id, uri + 5, len);
+	id[len] = '\0';
+
+	return id;
+}
+
+SPObject *
+sp_uri_reference_resolve (SPDocument *document, const gchar *uri)
+{
+	gchar *id;
+
+	id = uri_to_id(document, uri);
+	if (!id) return NULL;
+
+	SPObject *ref;
+	ref = document->getObjectById(id);
+	g_free(id);
+	return ref;
+}
+